OAI/Geometry/RCD/Harmonic/AffineChange.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

Least-squares affine fits are independent of coordinate normalization

  1. theorem OAI.RegularPointCoordinates.affineCoordinateSpace_eq_of_change line 18

    Source documentation

    An invertible linear coordinate change and a translation by constants preserve the actual finite-dimensional affine subspace in local L².

    theorem affineCoordinateSpace_eq_of_change {n : ℕ}
        (u u' : Fin n → SobolevSpace μ hQ) (s : Set X) (hfin : μ s ≠ ∞)
        (B : Euclidean n ≃L[ℝ] Euclidean n) (b : Euclidean n →L[ℝ] ℝ)
        (hchange : ∀ v, SobolevSpace.restrictLp μ hQ s (sobolevColumnMap μ hQ u' v) =
          SobolevSpace.restrictLp μ hQ s (sobolevColumnMap μ hQ u (B v)) +
            b v • restrictedOne μ s hfin) :
        affineCoordinateSpace μ hQ u' s hfin = affineCoordinateSpace μ hQ u s hfin := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.SobolevSpace.restrictLp, OAI.RegularPointCoordinates.sobolevColumnMap, OAI.RegularPointCoordinates.restrictedOne, OAI.RegularPointCoordinates.affineCoordinateSpace

  2. theorem OAI.RegularPointCoordinates.affineProjection_eq_of_change line 45

    Source documentation

    Consequently the least-squares projection itself is unchanged.

    theorem affineProjection_eq_of_change {n : ℕ}
        (u u' : Fin n → SobolevSpace μ hQ) (s : Set X) (hfin : μ s ≠ ∞)
        (B : Euclidean n ≃L[ℝ] Euclidean n) (b : Euclidean n →L[ℝ] ℝ)
        (hchange : ∀ v, SobolevSpace.restrictLp μ hQ s (sobolevColumnMap μ hQ u' v) =
          SobolevSpace.restrictLp μ hQ s (sobolevColumnMap μ hQ u (B v)) +
            b v • restrictedOne μ s hfin) :
        affineProjection μ hQ u' s hfin = affineProjection μ hQ u s hfin := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.SobolevSpace.restrictLp, OAI.RegularPointCoordinates.sobolevColumnMap, OAI.RegularPointCoordinates.restrictedOne, OAI.RegularPointCoordinates.affineProjection

  3. theorem OAI.RegularPointCoordinates.affineResidual_eq_of_change line 55